Patents by Inventor Fredrik Hagg

Fredrik Hagg has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Pickling agent containing urea and method of producing it
    Patent number: 6844304
    Abstract: A long-time stable pickling agent for the removal of an oxide layer on a stainless steel after heat treatment, such as welding, which pickling agent comprises nitric acid and fillers and constitutes of a pickling paste or pickling gel to be coated on the heat treated stainless steel, or of a pickling liquid to be sprayed on the steel. According to the invention, the pickling agent also comprises urea for reduced formation of nitrous fumes when the pickling agent is used.
    Type: Grant
    Filed: January 12, 2001
    Date of Patent: January 18, 2005
    Assignee: Avestapolarit Aktiebolag (Publ)
    Inventors: Sven-Eric Lunner, Fredrik Hägg
  • Picking agent containing urea and method of producing it
    Publication number: 20030004080
    Abstract: A long-time stable pickling agent for the removal of an oxide layer on a stainless steel after heat treatment, such as welding, which pickling agent comprises nitric acid and fillers and constitutes of a pickling paste or pickling gel to be coated on the heat treated stainless steel, or of a pickling liquid to be sprayed on the steel. According to the invention, the pickling agent also comprises urea for reduced formation of nitrous fumes when the pickling agent is used.
    Type: Application
    Filed: June 26, 2002
    Publication date: January 2, 2003
    Inventors: Sven-Eric Lunner, Fredrik Hagg